Driver Owns Buffer

#include <iostream>
using namespace std;

class Buffer {
private:
    int data;

public:
    Buffer() : data(0) {
        cout << "Buffer created" << endl;
    }

    ~Buffer() {
        cout << "Buffer destroyed" << endl;
    }

    void write(int value) {
        data = value;
    }

    int read() const {
        return data;
    }
};

class Driver {
private:
    // Composition: Driver owns the Buffer
    Buffer buf; 

public:
    // Constructor: Prints initialization and writes the value to the buffer
    Driver(int value) {
        buf.write(value);
        cout << "Driver initialized" << endl;
    }

    // Destructor: Observes the shutdown sequence
    ~Driver() {
        cout << "Driver destroyed" << endl;
    }

    void print() const {
        cout << "Stored value: " << buf.read() << endl;
    }
};

int main() {
    int value;
    if (!(cin >> value)) return 0;

    // Local scope to trigger destruction
    {
        Driver drv(value);
        drv.print();
    } // drv goes out of scope here

    return 0;
}